Since liquid crystalline resins have well-balanced properties among high flowability, mechanical strength, heat resistance, chemical resistance and electrical properties, they have been widely used as high function engineering plastics; and most of them are used for injection molding. Recently, the applications of the liquid crystalline resins have tended to become more advanced and specialized, and it is expected that blow-molded articles having excellent physical properties of the liquid crystalline resins can be efficiently and economically molded by blow molding the resins. For example, since pipes, vessels and the like used under a high temperature atmosphere are required to have high mechanical properties in addition to high heat resistance, they have hitherto been made of metals. However, for the purpose of weight saving, corrosion prevention, production cost reduction and the like, it is desired to produce them by blow molding the liquid crystalline polyester resins. Although the liquid crystalline polyester resins have high flowability and physical properties, they generally have low melt-tension, which is the most important property for applying blow molding, and thus they cause severe drawdown. It is therefore very difficult to obtain molded articles having a desired shape by blow molding the resins. In order to improve this disadvantage, a method using a polyester resin with a high polymerization degree, which has high intrinsic viscosity; a method using a branched polyester; a method adding various fillers, and the like are proposed, but all of them can have only small improving effects, and the materials are inadequate for these processing methods.
In order to solve the disadvantage, JP-A 6-306261 proposes a method, for the purpose of preventing drawdown of a parison, that a liquid crystalline resin is mixed with a styrene-based copolymer comprising styrene, a glycidyl ester of α,β-unsaturated acid and, if necessary, other vinyl-based monomers to improve a melt-tension of the liquid crystalline resin.
However, the method sometimes cannot be used for large-seized molded articles which require more excellent drawdown-resistant property, or molded articles which require severe properties such as further uniformity of thickness, yet.